Methodology

Geography

Income tax rates follow non-Scottish defaults. If you are tax resident in Scotland, use the Scottish bands on GOV.UK — Scottish Income Tax.

National Insurance

Employee NIC uses an illustrative 8% above the personal allowance threshold; employer NIC uses 13.8% on the same slice for transparency on total cost. Exact primary/secondary thresholds should be taken from HMRC each tax year.

Corporation tax marginal relief

We interpolate between the small profits rate (19% up to £50k) and the main 25% rate at £250k. Real filings must use HMRC’s marginal relief fraction per Finance Act provisions.

Dividend tax

The £500 dividend allowance is applied, then 8.75% / 33.75% / 39.35% slices are stacked after other taxable income — still a simplification versus real self-assessment stacking orders.